Standard: JG /T 5057.21 - 1995
Available sizes: M12 to M24 (7 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| M12 | 2 | 8.5 | 9.7 | 23.35 | 21 | 15.1 | 14 | 12.8 | 12.1 | 19.6 | 20.67 |
| M14 | 2.5 | 10.6 | 12.1 | 29.56 | 27 | 19.5 | 18 |
| 15.8 |
| 15.1 |
| 24.8 |
| 26.16 |
| M16 | 2.5 | 12.7 | 14.5 | 37.29 | 34 | 23.7 | 22 | 19.4 | 18.1 | 31.4 | 33 |
| M18 | 3 | 15.8 | 18 | 45.2 | 41 | 29.1 | 27 | 23.8 | 22.5 | 38 | 40 |
| M20 | 3.5 | 19.2 | 21.9 | 55.37 | 50 | 35.6 | 33 | 28.7 | 27.4 | 46.6 | 49 |
| M22 | 4 | 22.3 | 25.4 | 66.44 | 60 | 42.2 | 39 | 33.4 | 31.8 | 55.9 | 58.8 |
| M24 | 4.5 | 22.7 | 25.9 | 72.02 | 65 | 45.4 | 42 | 34 | 32.4 | 60.6 | 63.8 |
Standard corrosion protection for indoor and mild outdoor environments.
Salt spray: 96–200 hours | RoHS compliant (trivalent chromium)
High-performance coating for automotive, marine, and harsh environments.
Salt spray: 720–1500 hours | Recommended for grade 8.8+
Heavy-duty protection for structural and outdoor applications.
Salt spray: 500–1000 hours | Thread tolerance adjustment required
Note for high-strength fasteners (Grade 10.9, 12.9): Electroplating processes require hydrogen embrittlement relief baking (minimum 4 hours at 200°C within 4 hours of plating). Contact our engineering team for grade-specific plating recommendations.
Request detailed technical specifications, material certifications, and availability information for your application requirements. Our engineering team can provide product recommendations, custom specifications, and technical documentation.
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